Page wide array printer

Abstract

The present disclosure discloses a page wide array (PWA) printer ( 20 ) particularly but not exclusively for performing print jobs while maximizing print bar performance uniformity within the printer. The PWA printer includes a print bar which can be moved laterally and a controller which causes the print bar to laterally move from a first to a second position and causes the nozzles within the print bar to print an image while the print bar is in the second position without modifying the lateral alignment of the image.

The invention claimed is: 
     
       1. A page-wide array printer for printing on a substrate an image made of columns of image data such that the first column of each image is positioned at a same predetermined position on a substrate, said printer including:
 a print bar along which a plurality of nozzles are provided, said nozzles dynamically adjustable in relation to a width of the substrate such that which of said nozzles is positioned over a lateral position of the substrate is adjustable, and 
 a controller operable to:
 select one nozzle among a subset of said nozzles; 
 transmit said image data to be printed to the print bar such that the first data column of the image is input to the selected nozzle and the remaining data columns of said image are input respectively to adjacent nozzles of said selected nozzle so that the nozzles can collectively print said image; and 
 position the print bar and the substrate relative to each other such that the selected nozzle is laterally positioned in alignment with the predetermined position on the substrate, 
 
 wherein said controller is to periodically dynamically adjust said nozzles, 
 wherein each time said controller periodically dynamically adjusts said nozzles, said controller selects the one nozzle among said subset of said nozzles, such that the first data column of the image is input to the selected nozzle, according to a predetermined rule, 
 wherein the predetermined rule is to select the one nozzle in a successive manner among said subset of said nozzles. 
 
     
     
       2. The page-wide array printer according to  claim 1 , wherein the controller is arranged such that it is statistically not always the same nozzle of said subset which is selected. 
     
     
       3. The page-wide array printer according to  claim 1 , wherein, at each nozzle selection, the nozzle selected is different from the nozzle selected at the previous nozzle selection. 
     
     
       4. The page-wide array printer according to  claim 3 , wherein each of the nozzles of said subset is successively selected one after another at each nozzle selection in a cyclic manner. 
     
     
       5. The page-wide array printer according to  claim 1 , wherein the controller is to perform said nozzle selection each time at least one predetermined condition is met. 
     
     
       6. The page-wide array printer according to  claim 1 , wherein the controller is operable to cause the print bar to print an image on the substrate while the selected nozzle is positioned in alignment with said predetermined position. 
     
     
       7. The page-wide array printer according to  claim 1 , wherein the predetermined rule is further to select the one nozzle among said subset of said nozzles as a different nozzle than the one nozzle most recently selected. 
     
     
       8. The page-wide array printer according to  claim 1 , wherein the subset of nozzles consists of a group of nozzles located at one end of said bar print. 
     
     
       9. The page-wide array printer according to  claim 1 , wherein a controller is further operable to:
 cause the nozzles to print a first image in a first lateral alignment on a substrate while the print bar is in a first lateral position; 
 laterally move the print bar from the first to a second lateral position; and 
 cause the nozzles to print a second image at the first lateral alignment while the print bar is in the second lateral position.